simple

2/4 died

I have purchased 4 of these waterproof DelTran chargers over the years. 2 of the 4 have stopped working. One shows no light at all when plugged in, the other shows a green light no matter what the charge state of the batter is that it is hooked up to. The two newest ones that I purchased about a year ago are still working.
I have an older DelTran battery tender plus and it still works. I like the idea of the water proof charger but just do not trust that they last.